Red kites and model aircraft

Hi all, I'm just trying to find some help and advice. I was out walking today and I watched as a model airplane flying group purposely flew their aircraft into the flight path of a red kite and anotherr bird of prey causing them to swerve. I was wondering if this is normal practice or even legal. The birds were out hunting and I got a video of one of the events. Any help on this would be great. PrayPray